O.E. Glukhova – Dr.Sc.(Phys.-Math.), Professor, Head of the Department of Radiotechnique and Electrodynamics, Saratov State University named after N.G. Chernyshevsky
D.A. Kolosov – Post-graduate Student, Department of Radiotechnique and Electrodynamics, Saratov State University named after N.G. Chernyshevsky
M.M. Slepchenkov – Ph.D.(Phys.-Math.), Associate Professor, Department of Radiotechnique and Electrodynamics, Saratov State University named after N.G. Chernyshevsky
This paper is devoted to a theoretical study of the optical conductivity and photovoltaic properties of three allotropic forms of borophene – triangulated, β12 and χ3, as well as an assessment of the prospects for the use of borophene for photovoltaic applications. The construction of atomistic models of 2D unit cells for triangulated, β12 and χ3 borophene was carried out using the SCC DFTB method in the DFTB+ software package. In our calculations, the Brillouin zone was divided using the Monkhorst-Pack scheme. To calculate the optical conductivity tensor, the Kubo–Greenwood formula was used. New physical effects were revealed based on the results of a study. For the first time it was found that a triangulated borophene may be promising in highly efficient photodetectors of ultraviolet (UV) radiation, since this material is absent outside the UV range. The two other allotropic borophene modifications are characterized by the presence of pronounced absorption peaks in the visible spectral range. All types of borophene are very different from graphene. Graphene has one pronounced peak in the UV region and in the visible region. The conductivity of graphene is characterized by one conduction quantum. Analysis of the calculated maximum values of the photocurrent showed that 2D material based on χ3 borophene сan be extremely promising as a sensitive element of solar cells. This 2D material showed the highest value of the integral photocurrent for the visible emission spectrum of 0.892 мА•см2 for AM0 solar spectrum and 0.742 мА•см2 for AM1.5G solar spectrum. In comparison with graphene, borophen shows a larger value of the integral value of the photocurrent of the visible range for the case of the absence of the atmosphere (AM0 spectrum) by 31.73%, and for the case of the presence of the atmosphere (AM1.5G spectrum) by 32.73%.
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